Assisted Hatching
For the first six days of life embryos remain within a hard shell-like structure
called the
zona pellucida. Assisted hatching is a micromanipulation technique in
which a small opening is gently made in the zona pellucida of three-day-old
embryos. This technique may be useful in women who have been unsuccessful with
IVF in the past, or in older age groups.
Embryo Freezing and Cryopreservation
Couples undergoing IVF can have high-quality embryos that are not transferred
and may be frozen for future use. This is known as embryo cryopreservation. Embryos can be
placed back into the uterine cavity (a "thaw" cycle) after being frozen for many
years. In this way, the couple can avoid repeating the egg retrieval process.
